Abstract 603: A high-throughput image cytometry-based screening method for the cytotoxic effect of drug compounds on 3D tumor spheroid

Abstract

Abstract Cancer is a disease caused by uncontrolled proliferation or division of abnormal cells in an organism. Traditionally, cancer cell proliferation is measured using a two-dimensional (2D) in vitro model by culturing and treating the cells in standard microplates to study inhibition and cytotoxicity effect of the drug compounds. After further testing the potential cancer drug candidates in the 2D environment, the investigation is often transferred to an in vivo model by measuring the change in three-dimensional (3D) tumor sizes in animals. Although the drug candidates can demonstrate promising inhibitory or cytotoxicity results in a 2D environment, similar effects may not be observed in a 3D environment, which physiologically has a closer resemblance to a human body. Therefore, cancer drug discovery research has demonstrated poor translation from in vitro to in vivo. Previous publications have demonstrated that growing cancer cells in the form of 3D tumor spheroids can be more predictive of the in vivo study outcomes comparing to the 2D cell culture method. Therefore, by investigating the effect of cancer drugs on 3D tumor spheroids, may improve the successful translation rate to in vivo animal study. In this work, we developed an image-based high-throughput screening method for 3D tumor spheroids on 384-well ultra-low attachment (ULA) round bottom microplates using the Celigo image cytometer. In order to validate this screening method, five experiments were conducted demonstrating comparable results in both 3D and 2D models. First, optimal cell seeding density for tumor spheroid formation is determined by investigating U87MG (glioblastoma) cell seeding number in respect to the desired spheroid size. Second, the dose response effect of 17-AAG in respect to spheroid size is measured to determine the IC50 value. Third, the effect of 17-AAG on the viability of tumor spheroid is investigated in a time-course study. Next, the developed high-throughput method is used to perform dose response measurement of 4 drugs (17-AAG, Paclitaxel, TMZ, and Doxorubicin) in respect to the spheroid size. Finally, the effect of the 4 drugs on tumor spheroid viability is measured. Each experiment is performed simultaneously in the 2D model, where 384-well flat bottom microplates are used. In the 2D adherent cell model, confluence percentage and direct cell count-based viability results are generated to compare to the 3D model. This proposed method allows an efficient process for more qualified drug candidates, which can reduce time and the financial burden of animal testing, as well as the overall time of the cancer drug discovery project. Citation Format: Leo Li-Ying Chan, Olivier Déry, Scott Cribbes, Dmitry Kuksin, Sarah Kessel. A high-throughput image cytometry-based screening method for the cytotoxic effect of drug compounds on 3D tumor spheroid. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 603.